From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.6 required=3.0 tests=BAYES_05,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 94ADAC433E0 for ; Sat, 8 Aug 2020 21:19:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6E6B5206C3 for ; Sat, 8 Aug 2020 21:19:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="dPSE6jVA" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726212AbgHHVT6 (ORCPT ); Sat, 8 Aug 2020 17:19:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46110 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726069AbgHHVT5 (ORCPT ); Sat, 8 Aug 2020 17:19:57 -0400 Received: from mail-lj1-x229.google.com (mail-lj1-x229.google.com [IPv6:2a00:1450:4864:20::229]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 21EAFC061756 for ; Sat, 8 Aug 2020 14:19:57 -0700 (PDT) Received: by mail-lj1-x229.google.com with SMTP id i10so5754004ljn.2 for ; Sat, 08 Aug 2020 14:19:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to; bh=Efx0eQPWFDiEtI3TMpmnl3HA23YdCerjflULEQ2RJss=; b=dPSE6jVA7mjuPzTNxz7AINP5VT9h+DzrV0Ec0uhoUIFyxSxyfHyAp47nfvYzzrM7A5 Y138f2WNlqWJmFImLQeDjvqPWOD25DpNemzzh0AtNYZCjtdtN8d/NFcczWPNkB1EDKt5 OnM99x2SaunnCXRk13Gtthe1ySAH6eAh3qiouksUx2RLxzhQlSLpBHekLUcV/ipvv0Y8 AlITUHXXf+FlK775AjSThvuq8UMLmyz8Ac24Im5TmYT9wMsPDyPiRN2SujuT62tO/4Br 9KGiDMxScnFMuoV/t3ntN4cmo9J/9b6To+2P5CjplNR/n8AHP6mxCEZklXKR3+oLHu3x IFFw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to; bh=Efx0eQPWFDiEtI3TMpmnl3HA23YdCerjflULEQ2RJss=; b=PbGk1zbo4RqzGBHasaHsVvX7LR6NrKm5XnVI3+1kv2CrKGWy+2kkPyWQx9ebJqnrZX af4Uw702eNJb59L0EQSbbFbcbLD2DGrQKEAAbPhXnQfcUFgu0soVFCWWxUAEqV3IhkRd KbMALuS5TgIQiiJ3aGlBk0FO6VFFuxshCTfYZImW2y+CT5XVuLsuuakTmWuu+MdxveZ2 Ywe1+f0MfJrTnxAiZK2lMX236PdQq4oJRN2cJLRXUBJ+G94M7pN7b6WEQDjnLHFd90CE 8Iwmx7h46yKbS9HOQmop8sqSlUO6boGRaQyV191Ho/rJPSflp0N05qLng+Lk33Orvs29 V6Tg== X-Gm-Message-State: AOAM532zsOpV/Kp3B1Kj7jy5Mpq1xw/HSbwtl1hJTOyDOJYYQcdf4m7L XQsZuPHWjc5Fe0A6LQK9AXtVH/uxn5R1f7PCxQJQRUOg X-Google-Smtp-Source: ABdhPJz21rq8Ak4JsVQJb5F74WIDOqcskKjz11cW15qaQtUrPiZDql02VsNKHjEXg/W6jyt4FxAgQlM0yTvqyS2fhOY= X-Received: by 2002:a2e:8904:: with SMTP id d4mr8593999lji.400.1596921594787; Sat, 08 Aug 2020 14:19:54 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: William Tambe Date: Sat, 8 Aug 2020 16:19:42 -0500 Message-ID: Subject: Re: delayed_put_task_struct() used through call_rcu() by put_task_struct_rcu_user() never gets called To: rcu@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Sender: rcu-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: rcu@vger.kernel.org On Sat, Aug 8, 2020 at 4:17 PM William Tambe wrote: > > On Sat, Aug 8, 2020 at 1:21 PM William Tambe wrote: > > > > I am having an issue in my kernel where delayed_put_task_struct() used > > through call_rcu() by put_task_struct_rcu_user() never gets called. > > I am able to trace this issue to invoke_rcu_core() not getting called > in __call_rcu_core() due to rcu_is_watching() always returning true. > > Any idea why I am seeing such an issue ? Also, the issue is not happening when using highres=off . > > > > > Any idea ?